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Artikel Jurnal
基于10 kV开关柜热场分析的温度监测点选取方法研究
开关柜上的一些关键部位，比如断路器触头，不能直接安装温度传感器，为了获取合适的温度传感监测点，以实现对开关柜的监测和保护；文中以KYN28A-12型10 kV开关柜为研究对象，建立开关柜三维物理模型，通过Ansys仿真，得到开关柜在额定工况下的温度场分布规律，初步为后续的监测点选取提供仿真理论基础。为应对开关柜复杂的运行条件，笔者对开关柜在环境温度、载流量等不同工况下进行温度场仿真，基于仿真结果和理论分析，最终综合选取了一些温度变化差异较大的母排节点作为温度监测点，并具体分析了这些监测点在不同工况条件下的温升影响差异，验证了文中选取的温度监测点的合理性。
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Artikel Jurnal
基于绝缘支柱组件的ZW32真空断路器防潮性能优化设计
为了提升ZW32真空断路器的防潮性能，文中提出了一种绝缘支柱组件设计方案，它能够防止机构室内的潮湿气体向绝缘支柱内壁、绝缘拉杆外表面聚集。基于设计的绝缘支柱组件，进行了三维电场及温度场分析，研制了新型ZW32真空断路器，并进行了样机试验验证。结果表明，设计的新型ZW32真空断路器绝缘性能及其他电气性能完全满足国网要求，样机的基本外形尺寸与现行的ZW32真空断路器一致，具有一定的经济性。
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Artikel Jurnal
基于耦合负压的改进型多端口中压直流断路器拓扑研究
柔性直流配电网的可靠性建立在成熟的中压直流断路器基础之上，然而直流断路器高昂的造价限制了其在配电网中的应用。为了降低直流断路器在配电网中的投资成本，结合耦合负压换流方式，设计了一种改进型多端口混合式直流断路器。首先，对现有直流断路器的拓扑结构进行了分析；然后，提出了改进型多端口混合式直流断路器的拓扑结构，对分断故障时的动作时序进行了设计；最后，基于Pscad/Emtdc搭建了四端环网型柔性直流配电网，仿真分析了改进型多端口混合式直流断路器切除双极短路故障时的暂态特性，得到了内部电压、电流的分布情况，验证了所设计的故障隔离时序的可行性。结果表明，改进型多端口混合式直流断路器可在3…
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Artikel Jurnal
强制对流条件下大电流固体绝缘开关柜的温升建模仿真与试验
自然对流条件下，大电流固体绝缘开关柜难以达到温升标准的要求，因此通常需要强制对流散热。为提高固体开关柜的电流等级及探索不同强制对流条件对柜内温升的影响规律，文中以某型12 kV、2 500 A的固体绝缘开关柜为研究对象，首先在有限元软件中建立电—热—流多物理场耦合模型，模拟了2 750 A电流（1.1倍额定值）下温升分布，并通过试验验证了仿真模型的准确性；进一步试验了3 150 A电流下的开关柜温升，发现无强制对流散热时，开关柜温升无法满足GB/T…
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Artikel Jurnal
新型加铁磁材料触头阴极斑点扩散研究
为满足短燃弧时间情况下真空灭弧室的开断需求，文中采用仿真与实验的方法，先根据“马鞍形”分布纵向磁场对真空电弧扩散有利的理论基础，设计了一种加铁磁材料的触头，通过有限元仿真得到其纵向磁场分布特性，接着采用工频触发电弧实验平台对比了新型触头与传统杯状纵磁触头的阴极斑点扩散过程。实验结果表明，加铁磁材料触头的阴极斑点运动到触头一半直径位置后速度有所降低，使之在触头边缘相对稳定燃烧，阴极斑点在触头边缘的密度与中心区域相差不大，阴极斑点覆盖区域较传统杯状纵磁触头更大。文中目前还是主要针对部分燃弧条件下真空电弧的燃弧过程尤其是初始扩散阶段，为短燃弧时间的真空断路器触头设计提供一定的参考。
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Artikel Jurnal
基于改进遗传算法的高压隔离开关主开关机构优化设计
水平伸缩式高压隔离开关因其占地面积小、产生断口明显，在高压电网中应用广泛。但其主开关机构在分合闸过程中产生较大的重力矩变化，除需配置合适的平衡弹簧，还需对结构进行优化设计，以减小机构所需驱动力矩。文中以550 kV交流高压隔离开关为对象，对主开关机构进行力学分析，并基于改进遗传算法对主开关机构进行优化设计、建立动力学仿真模型并进行验证，确定高压隔离开关工作时所需电机驱动力矩的最小值。结果表明，改进遗传算法相比传统方案所需最大电机驱动力矩减小22%，驱动力矩变化量减小43%。优化后的水平伸缩式高压隔离开关主开关机构传动部件受力及动作过程中力矩变化量减小，进而提高高压隔离开关分合闸动作的平稳性。
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Artikel Jurnal
An Assessment of the Productivity Challenges Experienced by Manufacturing Small Micro Medium Enterprises During Lockdown
The focus of this study was to examine productivity issues experienced by small, medium and micro enterprises (SMMEs) in the manufacturing sector in Ekurhuleni Municipality during COVID?19 lockdown restrictions, more particularly focusing on internal and external environment factors influencing the…
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Artikel Jurnal
Cracking the Financing Gap: How Informal Traders in Zimbabwe are Bridging the Banking Divide
In Zimbabwe, informal traders face significant barriers in accessing formal financial services, hindering their ability to grow and sustain their businesses. However, these traders are finding innovative ways to bridge the banking gap by leveraging alternative financial services. The paper…
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Artikel Jurnal
Factors Affecting the Financial Performance of the Samarinda City Regional Government
Purpose: This study aims to analyze the effect of the effectiveness ratio and efficiency ratio on the financial performance of the Samarinda City Regional Government, as well as to test whether the regional financial independence ratio plays a mediating variable in the relationship between the…
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Artikel Jurnal
How AI Impacts Entrepreneurs’ Psychology: Self-Efficacy, Technostress, Dependency, and Work Engagement (A Literature Review)
The rise of artificial intelligence (AI) presents entrepreneurs with unique yet significant psychological challenges and opportunities that remain underexplored. This literature review examines the impact of AI adoption on entrepreneurs’ psychological well-being, performance, and work engagement…
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Artikel Jurnal
Application of the Principles of Good Faith and Pacta Sunt Servanda in Unequal Construction Contracts: A Case Study of B2B Developer–Contractor
The legal relationship between developers and contractors in business-to-business (B2B) construction contracts in Indonesia often shows a significant imbalance of power. Although formally the contract is made based on the principle of freedom of contract, substantively the legal relationship often…
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Artikel Jurnal
THE EFFECTIVENESS OF CONSTRUCTION GOODS AND SERVICES PROCUREMENT LAWS ON PRIVATE CONTRACTORS: A LEGAL SYSTEM PERSPECTIVE LAWRENCE M. FRIEDMAN
Public procurement of construction works constitutes a strategic instrument for national development; however, in practice it continues to face complex legal problems. These problems do not merely arise from procedural violations or corrupt intent, but also from unclear administrative authority…
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Artikel Jurnal
Marketing Management: Present, Past and Future in the Modern Business Scene
Marketing management has undergone substantial transformation in response to economic development, technological innovation, globalization, and evolving consumer behavior. Initially rooted in production efficiency and transactional exchanges, marketing management has progressively evolved into a…
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Artikel Jurnal
Legal Risks of Land Use and Spatial Planning in Development by Private Developers and Contractors in Indonesia: Normative Analysis, Case Studies, and FIDIC Contract-Based Mitigation Strategies
This article aims to comprehensively analyze the legal status of land use and spatial planning as a source of legal risk in construction projects, as well as its implications for private developers and contractors. This study uses a normative legal research method with a statutory, conceptual, and…
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Artikel Jurnal
Optimizing Employee Performance of the Central Statistics Agency through Transformational Leadership, Training: Job Satisfaction Mediators
Performance is a real behavior displayed by each person as a perception of work by employees according to their role in the company. This study aims to determine the relationship between the influence of transformational leadership, job training, job satisfaction and employee performance of the…
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Artikel Jurnal
Profitability Ratio Analysis to Measure Financial Performance
Purpose: This research aims to evaluate the profitability ratios of companies in the Food and Beverage sector listed on the Indonesia Stock Exchange (IDX) from 2021 to 2024. The study specifically focuses on analyzing the Return on Assets (ROA), Return on Equity (ROE), Net Profit Margin (NPM), and…
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Artikel Jurnal
Prevalence of Probable Generalised Anxiety Disorder Among Master of Public Health Students at the University of Ibadan, Nigeria
Introduction: Generalised anxiety disorder (GAD) is a common and debilitating mental health condition characterised by excessive and persistent worry over various aspects of life. GAD poses significant challenges for university students, affecting their physical health, academic performance, and…
Juga tersedia di: DOAJ
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Artikel Jurnal
Safety and Effectiveness of Intravenous Ferric Carboxymaltose for Moderate Anaemia in Pregnancy
Background: Anaemia in pregnancy is a major global health concern linked to adverse maternal and foetal outcomes. Intravenous ferric carboxymaltose (FCM) is a relatively new therapy that enables rapid correction of iron deficiency with minimal adverse effects. Aim: To evaluate the safety and…
Juga tersedia di: DOAJ
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